Relay



' 1,632,186 June 14, 1927. E. G. JOHNSON RELAY Filed Deo. 50. 1922 2Sheets-Sheet 1 www RELAY Filed Dec. 30. 1922 2 'sheets-sheet 2 PatentedJune lll, H32?.

MENTS1 T0 TEE ALMER ELECTR BREDGE, MASSACHUSETTS, A CORZSQE wir RELAY.

Application filed December 30, 1.922.

This invention relates to relays more particularly intend-ed forcontrolling' circuits in response to changes in energy conditions ot therelay circuits which mayor may notbe derived from the controlledcircuits. For this purpose the relay ot the present invention isprovided with a member movable in response to energy changes in therelay circuit and subjected at certain positions only to other forcesmodifying the movement otherwise imparted to the member by such energychanges.

Ther invention is herein exempliiied in a relay constructed to open acircuit on both the rise and iall of voltage ot the relay circuit topredetermined values, the other forces above mentioned acting to eltecta Quick opening and closing ot the controlled circuit and to prevent theclosing of the controlled circuit after it has been opened, except at apredetermined voltage change from the high or low circuit opening valuestoward an intermediate value. This latter eiriiectually preventsfluttering or hunting` oit the circuit closer because oi' slight rapidiiuctuations in the voltage ot the relay circuit The controlled circuitmay? it desired, be en'iployed to impart correcting` influences 'torregulating` and maintaining' closely at a desired value the voltage ot alighting or power main circuit, or it may be desired to utilize thecontrolled circuit only when its voltage lies within a desired limitedrange, the energy conditions ot'the relay circuit boing maderesponsivein the iirst instance to the voltage ot the lighting or powercircuit and in the second instance to that of the controlled circuit.

Other valuable uses of this relay will suggest themselves to thoseskilled in the art.

For a more complete understandino,` of this invention', .reference bekhad to the accoinpanyiiig` drawings in which Figure 1 is a. sideelevation ot a relay einbodyingthe invention.

Figure 2 is a front elevation or" the saine,

ire is a fragmentary detail.

Fi ires l and 5 are 'fragmentary 'front elev ons showing` the switch torthe controllen circuit opened by too high and too low voltagerespectively.

Serial No. 699,896.

's a diagram showing the electo Figure (i, 1 represents a cesiwned to beoperated by a cona circuit and only when the voltage circuit lies withinpredetermined l g one exemplication ot the invention. ris shown one of 2one sid-e ot a source of power 8 and the o terminals ot the motorconnects Contact T being normally biased to closed po. on as by means ofits weight. It is evident then that when the switch a is closed theswitch t is also closed and the inotoi circuit closed. Should the switcha open, however. the motor circuit is immediately opened by the switch4. The opening of the switch (t is controlled by a relay circuit whichas shown also derives its energyfrom the source ot power 3 and hastherein a solenoid 10.

Referring; now to Figures 1 and 5 the solenoid 10 is shown as fixed invertical position to a base or panel board 11 and has slidable therein amagnetic core 12 the weight ot' the core tending to draw it out ot thesolenoid. To eliminate any sticking or trictional dragv between the core12 and the solenoid, guide rods 13 are shown as projecting; downwardlyfrom the solenoid and the lower end ot' the core has lixed thereto aguide bar 14 engaging' tli'ese rods and to whi vh is i'ixec an outwardlyentendinc' angle piece 15. The switch arm T has adiustably fixed thereina screw 16 which is adapted to be struck by the angle member .1.5 whenthe core 12 is raised sutliciently within the solenoidl` thus to raisethe arm 7 and open the switch a. The arm 7 also has fined thereto anadjustable screw abutment 17 which rests upon a lever arm 18 ful crumedat 19, this fulcrum as shown being carried by a U shaped member 2O fixedto the outer end of a bracket arm 21 attached to the forward face ot thepanel board 11. At the opposite side of the fulcrum 19 from the abutment17 the lever arm 18 carries a screw 25 the upper end ot' which may bestruck by the angle member 15 on the descent of the core 12l` so thatthe arm 18 may be rocked and the abutment member 17 raised causing theswitch element to be raised and its contact with the member 6 broken.

It is well known that solenoids may be so designed that their cores mayfloat therein and if biased to move outwardly thereof to be moveddefinite distances by definite changes of voltage imposed on thesolenoid. Hence the position of the core 12 within the Solenoid isdependent upon the energy impressed on the solenoid so that should theenergy approach a suiiiciently high value, the core will be raisedsiniiciently to open the switch a, or if the energy falls to apredetermined point the core 12 is permitted to fall sufficiently toopen the switch o. As shown the arm 7 of the switch is counterweightedby the weight and an adjustable stop screw 31 is provided to limit theopening movement of this arm.

Should the construction above outlined be employed without modificationtor opening or closing the switch a it is evident that the switch wouldbe opened at the attainment of a certain definite voltage in thesolenoid, but shouldV this voltage fall a very small amount, the switchwould be allowed to close again. Thus if small energy changes wereimpressed on the solenoid, the switch 7 would be caused to open andclose rapidly, thus causing a fluttering action of the entire mechanismand causing the motor 1 to be energized and deenergized rapidly. Undersuch conditions this motor would be liable to be damaged. In order toprevent such a fluttering or hunting action and further in order torelieve the normal torce of the solenoid on the core 12 from thc duty ofopening the switch, the following mechanism has been provided.

Within the upper end of the solenoid is adjustably positioned a stopperof magnetic material. This may be adjustably fixed in vertical positionby means oi a set screw 41, threaded in a block 42 fixed to the panel11.y This stopper has an opening for the slidable reception of a guiderod 43 of non-magnetic material fixed within the upper'end of the core12. This holds the upper end of the core out of: engagement with theinner' face of the solenoid coil, thus preventing it from catching'thereon or being frictionally retarded thereby. This stopper is soadjusted vertically in the selenoid that immediately before the corereaches its upper position at which the switch 7 is to be opened, itcomes within the magnetic field of' the stopper 40 caused by the energyimposed on the solenoid Then this takes place, this magnetic fieldeffects a sudden upward impulse to the core 12, imparting thereto aforce to cause the angle piece 15 to strike sharply against the screw 16and open the switch arm. The stop screw 31 and the stopper 40 are soadjusted that the core 12 may not actually contact the lower end of thestopper 40 and the air gap between the stopper and the core maybedetermined as desired.V This relative position of the core and stopperwhen the switch a is in open position is illustrated in Figure 4. Thisconstruction not only insures an additional force being imparted toeilect the opening of the switch a. but also causes a holding effect tobe imparted to the core to retain it at its upper limit of motion untilthe energy imparted to the solenoid has decreased to a value somewhatbelow that requiredto bring it initially into the field of 'torce of thestopper. When this condition occurs the core drops away suddenly per"mitting the switch (L to close quickly. The amount of the air gapbetween the stopper and the coredetermines the amount to which theenergy impressed on the solenoid must be reduced after the switch a hasbeen opened by the movement of the core 12 to its upward limit of motionbefore this core can descend due to its weight, and permit the switch ato close.

Likewise when the switch is opened by the falling of the core on apredetermined decrease in the energy impressed on the sole-l noid, meansis provided for imparting an additional force to the solenoid foropening the switch a and for holding it open until energy impressed onthe solenoid is raised to a point above that at which the switch isopened. For this purpose the bracket 21, beforementioned, has adjustablythreaded therein a plug or block 45 of magnetic material (seeparticularly Figure B) so that as the core descends, due to a decreaseof energy in the solenoid, it approaches the upper end of the block 45,which thereupon hecomes magnetized from the lines of force extendingfrom the lower end ofthe core. As this block 45 is held stationary thismagnetic force immediately results in a downward pull against the core12 so that the angle member 15 impinges on the screw 25 with a suddenblow and causes the switch arm 7 to be suddenly pushed upwardly to openthe switch. a. Here again it is desirable to adjust the air gap betweenthy, lower end of the core 12 and the plug or block 45 and for thispurpose a nonmagnetic abutment screw 46 is threaded therethrough andagainst the upper end of which the core 12 impinges. The adjustment ofthis screw determines the air gap and therefore determines the increaseof energy which must be imparted to the solenoid to cause the core 12 tobe separated trom the iield of influence of the plug i5 so as to beraised quickly into position to permit the switch o to close. To holdthe plug in adjusted position its lower end may have threaded thereon alock nut e7.

lt will be seen that the torce imposed by the magnetized plug at theupper end ot the solenoid acts on the core in the same direction as anincreased energiZat-ion of the solenoid and that the torce imposed bythe magnetization of the lower block Ll5 acts in opposition to theenergization of the solenoid or in the same direction as adecreasedenergization thereof.

Having thus -described an embodiment of this invention it should beevident that many changes and modifications may be made therein withoutdeparting from its spirit or scope as defined by the appended claims.

l claim:

l. In an electrical relay, a Contact member y biased in one direction, amember movable tl O in response to changes or' energy conditions andoperative at deiinite limits of motion to move said contact member outot its biased position, and means tor imposing on said movable member'when adjacent said limits or" motion forces modifying its movement inresponse 'to said changes ot' energy conditions.

2. ln combination, a normally closed contact member, a member movable inresponse to changes ot energy condition in a circuit and operative atpredetermined limits of its motion to open said contact member', andmeans for imposing on said member adjacent said limits forces actingwith relation to the -energy changes in said circuit to ellec-tsudden'movements ot' said member when adjacent said limits toward and'from said limits.

3. ln combination, a normally closed contact, a member movable inresponse to energy changes in a circuit and operative adjacent limits ofits motion to open said contact, and means ior causing the energy insaid circuit to exert a drawing and holding etlect on said member whenadjacent said limits toward the respective limits.

ln combination, a member movable in response to energy changes .in acircuit beletermined limits, means ttor causing in said circuit to exerta drawing and Y eliiect on said member when adjacent either et saidlimits toward the respective limits, and a device actuated by themovement ot said member only when adjacent to said limits,

5. ln an electrical relay, a normally closed switch, a member responsiveto energy changes acting to open said switch at'determined 'maximum andminimum energy values, and means acting to prevent the closing tooperate said device from said condition at determined maximum andminimum energy values, and means 'for preventing the return ol saiddevice to its normal condition until the energy shall have reachedvalues ot determined differences trom and intermediate of said maximumand minimum.

7. A relay comprising a switch normally biased to closed position,electromagnetic means for opening said switch at -determined maximum andminimum enero'ization, and means for preventing the closing of saidswitch until the cnergization shall have reached one or the other ofvalues intermediate oi" and at predetermined differences from saidmaximum and minimum.

8. A relay comprising a switch normally biased to closed position, asolenoid, a magnetic core movable in said solenoid and normally biasedaway `from the center thereof to be movable in opposite directionsbetween limits by energy changes in said solenoid between determinedhigh and low values1 means for effecting the opening of said switch onmovement of said core to either of its limits, and magnetic materialfixed beyond the ends of said core and within the limits of the magneticfield at the corresponding end when said core is adjacent its limit ofmotion in either direction.

9. A relay comprising a switch normally biased to closed position, anupright solenoid, a core vertically movable in said solenoid to be drawnupwardly therein when said solenoid is sniiiciently energized and tofall therefrom when the energy falls, means for opening said switch whensaid core rises to a. predetermined extent, means tor opening saidswitch when said core falls to a predetermined extent, a magneticelement in said solenoid into the field of torce of which the upper endof said core moves as it approaches its upper limit of motion, and anelement of magnetic material fix-ed beneath the lower en'd of said coreand within the magnetic iield ot said core as said core approaches itslower limit ot motion.

l0. A relay comprising a switch normally biased to closed position, anupright solcnoid, a core vertically movable in said solenoid to be drawnupwardly therein when .aid solenoid is sutiiciently energized and totall therefrom when the energy falls, means tor openingsaid switch whensaid cor-e rises to a predetermined extent, means Jr'or opening saidswitch when said core falls toa predetermined extent, a magnetic elementin said lower limit of motion, and means for adjustsolenoid into thefield of force of which the ing the air gaps between said core and saidupper end of said core moves as it approaches elements at the limits ofmotion of said 10 its upper limit of motion, and an element of core.

magnetic material fixed beneath the lower In testimony whereof I haveaffixed my end of said core and within the magnetic signature.

field of said core as said core approaches its ERNEST G. JOHNSON.

